Pipe cutting apparatus

ABSTRACT

Apparatus for cutting pipe having inner and outer surfaces, comprises: A. DRIVE MEANS ENGAGEABLE WITH ONE OF SAID INNER AND OUTER SURFACES FOR ROTATING THE APPARATUS ABOUT THE PIPE, B. THRUST EXERTING MEANS ENGAGEABLE WITH THE OTHER OF SAID INNER AND OUTER SURFACES FOR URGING THE DRIVE MEANS TOWARD SAID PIPE, SAID THRUST EXERTING MEANS INCLUDING INDIVIDUALLY ADJUSTABLE ROLLERS ENGAGEABLE WITH SAID OTHER SURFACE, C. SUPPORT STRUCTURE FOR SAID DRIVE MEANS AND THRUST EXERTING MEANS, D. A FIRST CUTTING TOOL AND A HEAD THEREFOR CARRIED BY SAID SUPPORT STRUCTURE FOR MOVEMENT TOWARD AND AWAY FROM SAID OTHER SURFACE OF THE PIPE, AND E. OTHER MEANS INCLUDING A SPRING TO YIELDABLY URGE THE HEAD TOWARD SAID OTHER SURFACE OF THE PIPE SO THAT THE CUTTING TOOL MAY HAVE YIELDABLE CUTTING ENGAGEMENT WITH THE PIPE AS THE APPARATUS ROTATES ABOUT THE PIPE.

United States Patent Bachmann [$41 PIPE CUTTING APPARATUS [72] inventor:George Bachmann, 945 Metro Drive, Monterey Park. Calif. 9 i754 [22]Filed: March 29, 1971 [21] Appl. No.: 128,953

[52] US. Cl. .3214 C, 82/76 [5i] Int. Cl. ..........B23b 3/22, B231)5/04. B23b 3/04 [58] Field of Search ..82/4 C, 70.2, 71, 72, 73, 74,

[56] References Cited UNITED STATES PATENTS 3,247,743 4/1966 Frost eta]. ..82/4 C 2,753,739 7/1956 Dreier ..82/4 C 909,l 82 1/1909 Hart..82/4 C Primary Examiner-Harrison L. Hinson AttorneyWhite, Haefliger &Bachand [is] 3,691,881 [451 Sept. 19,1972

[57] ABSTRACT Apparatus for cutting pipe having inner and outersurfaces, comprises:

c. support structure for said drive means and thrust exerting means,

d. a first cutting tool and a head therefor carried by said supportstructure for movement toward and away from said other surface of thepipe, and

e. other means including a spring to yieldably urge the head toward saidother surface of the pipe so that the cutting tool may have yieidablecutting engagement with the pipe as the apparatus rotates about thepipe.

PATENTEuszr 19 I972 3.691.881

SHEET 1 BF 3 2 W fluu/ PAIENTED EH m2 3.691.881

SHEET 3 [If 3 f/vvEA/roz 245, n/afl PIPE CUTTING APPARATUS BACKGROUND OFTHE INVENTION This invention relates generally to apparatus for cuttingpipe; more particularly, it concerns pipe grooving and cut-off apparatusof improved construction and mode of operation.

There is a need for easily operable and highly reliable equipment forgrooving and/or cutting-off metallic pipe of a wide range of diameters,and which can be used on the jobsite. While attempts have been made inthe past to meet this need, no apparatus of which I am aware embodiesthe unusually advantageous features of construction, modes of operationand beneficial results afforded by the present invention, as will beseen. Among these are the capacity for both grooving and cutting-offpipe, as optionally required; portability; spring loading andsimultaneous adjustability of the cutter or cutters; integration of allfeed and tension controls at one location; improved adjustable mountingof the tool on the pipe for rotation about the pipe during grooving;cutting rate control; capacity for location of the grooving tool at anadjustable distance from the end of the pipe; and additional advantagesas will be seen.

SUMMARY OF THE INVENTION It is a major object of the invention toprovide pipe cutting apparatus embodying the above advantageousfeatures, modes of operation and results. Basically, the apparatuscomprises, in combination, drive means engageable with one of the innerand outer surfaces of the pipe (as for example, the inner surface) fordriving the tool about the pipe; thrust exerting meansincludingindividually adjustable rollers engageable with the other pipe surface(as for example, the outer surface) for holding the drive means on thepipe, there being a body or support for the drive and the rollers; afirst cutting tool and head therefor carried by the support structurefor movement toward and away from the opposite surface of the pipe; andmeans including a spring to yieldably urge the head toward that othersurface of the pipe so that the cutting tool may have yieldable cuttingengagement with the pipe as the tool rotates relative to the pipe. Inthis regard, the tool may rotate about the pipe axis.

More specifically, a second cutting tool may be carried by the head foralternate cutting presentation to the pipe, and the cutters mayrespectively comprise a groove cutter and a pipe cut-ofi element; thespring may be supported by a first carrier for adjustable movementtoward and away from the pipe to control spring force transmission tothe cutting tool; a second carrier may be operatively connected with thehead for adjustable movement displacing the head. toward and away fromthe pipe while the spring continues to urge the head toward the pipe;the thrust exerting means may comprise pairs of rollers engageable withthe pipe outer surface, and holders for the roller pairs individuallycontrollably movable along arcuate paths to advance and retract therollers generally normal to the pipe surface; certain rollers may beperipherally grooved to urge the support structure endwise toward thepipe end; and there may be provision for adjustable spacing of groovecutting from the pipe end.

These and other objects and advantages of the invention, as well as thedetails of an illustrative embodiment, will be more fully understoodfrom the following description and drawings, in which:

DRAWING DESCRIPTION FIG. I is a top plan view of apparatus incorporatingthe invention;

FIG. 2 is a front elevation taken on line 2-2 of FIG.

FIG. 3 is a section taken in elevation on lines 3-3 of FIG. 2;

FIG. 4 is a section taken on lines 4-4 of FIG. 2;

FIGS. 5 and 6 are sections taken on lines 5-5 and 6-6 respectively ofFIG. 4;

FIG. 7 a horizontal section taken on line 7--7 of FIG.

FIG. 8 is a vertical section taken on lines 8-8 of FIG; 3; and

FIG. 9 illustrates two grooved pipes retained in endto-end relation.

DETAILED DESCRIPTION In the drawings, a support structure may, forexample, include a body 10 and vertically extending, horizontallyspaced, front and back cover plates I I and 12. Drive means carried bythe support structure may typically include a spur gear 13 attached toshaft 14 projecting at for driven connection with a rotary power source15; a larger spur gear 16 (for speed reduction) meshing with gear 13 andcarried by shaft 17; and pipe engaging roller 18 carried and driven byshaft extension 17a. Two nuts 19 and 19a threaded on extension retainthe roller 18, and a key 20 interconnects the roller and the extension170.

Roller 18 may typically be serrated or toothed at to positively grip anddrive one surface (as for example, inner surface 21) of a pipe 20 to besubjected to grooving and/or cutting. As will be explained, when thetool is rotated about the pipe by the roller I8, for example, in thedirection of arrow 23 in FIG. 2, a stop flange 25 carried on the roller18 or shaft 17 is urged relatively against pipe end 24. This enablesaccurate spacing, from the end 24 of the pipe, of the groove cut in thepipe wall by the tool. FIG. 9 shows two such grooves 26 and 27 formed inadjacent pipes 28 and 29 held in endto-end relation by a suitablecoupling 30.

Also provided is what may be generally referred to as thrust exertingmeans engageable with the pipe opposite surface (as for example, outersurface 31) for urging the drive roller toward and into engagement withthe pipe. The illustrated thrust exerting means includes a pair of guideroller units 32 and 33 engageable with the pipe outer surface as bestseen in FIG. 2, and holders for these roller units movable on andrelative to the support structure along arcuate paths to advance andretract the rollers generally normal to the pipe outer surface.

More specifically, and as seen in FIGS. 4-6, the roller unit 32 includesrollers 32a and 32b integral with a common shaft 34. A holder yoke 35between the rol- Iers contains a bore 36 to closely receive the shaft 34for displacing same along the described arcuate path defined by thearcuate guide slot 37 in plate 11. An extension 34a of the shaft passesthrough the slot, and projects into the body interior 38 for pivotalconnection to link 39. The latter swings about pivot hinge 40 to supportshaft 34 and the rollers 32a and 32b for arcuate movement as described,pivot hinge 40 being supported by plates 11 and 12. Such movement iscontrolled as by the feed screw 41 carried by body projection 42. Thescrew has connection to a threaded sleeve 43; and its lower terminal 44is rotatably connected at 45 to the holder so that when the handle 46 onthe screw shaft upper end is rotated, the holder 35 and rollers 32a and32b are displaced along the arcuate path defined by slot 37, or byswinging of link 39.

Similarly, the roller unit 33 includes rollers 33a and 33b integral witha common shaft 54. A holder yoke 55 between these rollers contains abore 56 to closely receive the shaft 54 for displacing same along thedescribed arcuate path defined by guide slot 57 in platell. An extension54a of the shaft passes through the slot and projects into the bodyinterior 38 for pivotal connection to link 59. The latter also swingsabout pivot hinge 40 to support the shaft 54 and the rollers 33a and 33bfor arcuate movement as described. A feed screw 61 also carried by bodyprojection 42 controls the swing of the holder 55 and rollers 33a and331) about hinge axis 60, which is generally parallel to the axis of thepipe 22 to be grooved. Screw 61 has connection to the interiorlythreaded sleeve 63; and its lower terminal is rotatably connected with aholder similar to holder 35, so that when handle 66 on the screw shaftupper end is rotated, the associated holder and rollers 33a and 33b aredisplaced along the arcuate (circular) path defined by slot 57, or byswinging of link 59.

It will be noted that each of the rollers 32a and 33a has surfacegrooving which extends circumferentially about the roller. Such groovingis angled, or spiraled, to engage and urge the support structure endwisetoward the pipe, and specifically the support structure comprises thestop flange 25 previously described. This occurs in response to rollerrotation as effected by turning of drive roller 18 urged into grippingengagement with the pipe interior surface by the rollers 32a, 32b, 33aand 33b forced against the pipe exterior surface. The use of two sets ofroller pairs as described stabilizes or "squares" the tool relative tothe pipe and its end 24, whereby an accurately located groove may be cutwith uniform depth. Positive urging of the stop flange toward the pipeend may also be aided by very slight angling of one of the roller axes32c and 330 out of parallel with the axis 180 of the drive roller 18, asbest seen in FIG. I. The illustrated divergent angle a is about V Line32d is parallel to axis 18a.

Also provided is a cutting tool head or post 70 guided for movementtoward and away from the pipe 22, as by the dove-tail corners 7 la and71b on a slide 71, which have slide interfit in the dove-tail recesses72a and 721: formed in support 73. The latter is attached to the plate Il, as by the fasteners 74.

ln this regard, the post 70 may be locked in any selected up and downposition as by tightening the set screw 75 which urges an angled gib 76laterally against the slide, as seen in H0. 7. Post 70 may be fastenedas at 69 to the slide. Alternatively, the post may be fastened in brokenline position 690 to the slide, for grooving only. (i.e., withoutcut-off.)

Means is provided to yieldably urge the slide and post, as well ascutting tool 77 carried by the post,

toward the pipe. Such means is shown to include a compression spring 78the lower end of which engages and urges the slide downwardly, and theopposite or upper end of which engages a shoulder 79 on a first carrier80 in the form of a sleeve. The latter had threaded engagement at 81with a plate 82 integral with the body 10, so as to support the upperend of the spring for movement toward and away from the pipe, thereby tovary the spring compression and downward force exertion on the slide. Aswill be seen, the spring generates the force yieldably urging the cutteragainst the pipe, and this force may be varied by rotating the firstcarrier 80. For this purpose, the carrier may be provided with a handle81.

A second carrier, as for example, may comprise rotor 83, is operativelyconnected with the post and carried by the first carrier sleeve foradjustable movement displacing the post toward and away from the pipewhile spring 78 continues to urge the head and cutter 77 toward thepipe. Carrier rotor 83 is shown as a sleeve having internal threadedconnection with the upper portion of a feed screw 84, the lower end ofwhich is attached to slide 71. When rotor sleeve 83 is turned, as bymeans of handle 99 to retract the screw and also the slide 71, post 70and cutter 77 away from the pipe, the spring force exerted on the slideis transmitted via the screw to the rotor 83 and urges it intoengagement with a thrust bearing 85 on the carrier 80; conversely, whenthe rotor 83 is turned in the opposite rotary direction to advance thescrew 84 and therefore the cutter 77 toward and into engagement with thepipe, the spring force is transferred to the cutter. Such transfer canbe determined by observing the disengagement of rotor 83 from the thrustbearing. Accordingly, accurate control of cutting force applicationgenerated by a heavy-duty spring is realized, for rapid and accuratepipe cutting.

Selective cutting, as for example, grooving and/or cutting-off, is alsoenabled by the invention. For this purpose, reference is made to FIG. 8showing the manner in which cutter 77 remains presented downwardly tothe pipe at all times, whereas a second cutter 86 is selectivelyswingable about pivot 87 on post 70 downwardly toward the pipe. In thelatter event, cutter 86 projects downwardly to greater extent thancutter 77, so that cutter 86 is operable rather than cutter 77. In thisregard, cutters 77 and 86 may respectively groove the pipe, andcut-through a pipe section, as the pipe rotates. Pivot 87 may comprise athreaded fastener which may be tightened to hold cutter 86 in swing-downposition.

Finally, a selected thickness spacer 90 may be inserted between groovecutter 77 and the post 70 to space the groove cutter at a selecteddistance from the end 24 of the pipe. Accordingly, control of the groovespacing from the pipe end is afforded.

Reference to FIG. 2 will also show the wide range of sizes of pipe thatmay be grooved or cut-off, by means of the present invention. Two suchlarger and smaller pipes are indicated at 20 and 100.

in operation, the apparatus is mounted on a pipe as shown on FIG. 3, andthe roller units 32 and 33 are individually adjusted to clamp the pipeinner wall against the drive roller or cylinder 18. At this time, thepost 70 may be in retracted position. Next, the carrier 83 is rotated toadvance the cutter downwardly into engagement with the pipe, and thecarrier is further turned to back away from thrust bearing 85. In thisregard, the extent of such back-off may be used to control the depth ofgrooving, the carrier 83 re-engaging the thrust bearing to limit furthercutting when the desired depth is achieved. Normally, however, anadjusting nut 91 on a threaded stud 99 carried by post '70 is used tolimit depth of cut by engagement with the top of plate 82.

For this purpose, stud 99 may project through an opening in that plate,as shown. Locking nut 98 locks adjusting nut 91 in selected position.Next, the cylinder 18 is rotated to effect pipe relative rotation andcutting.

It should also be noted that provision for individual adjustability ofadvancement of the roller pairs 32 and 33 toward and against the pipeserves as a means to control the angle of attack of the operative orselected cutter relative to the pipe, for cutting rate control. Thus, inFIG. 2, if rollers 33 are advanced toward the pipe and rollers 32retracted, the cutting edge 90 will have a larger angle of attackrelative to the pipe outer surface.

The spring 78 tends to prevent jamming due to the fact that the cutterand post 70 are able to move outwardly relative to the pipe and againstspring compression should cutting resistance approach drive forcetransmitted to the pipe by the roller 18. Rollers 32 and 33 may then beadjusted to decrease the cutter angle of attack, to relieve the jammingtendency.

lclaim:

1. ln apparatus for cutting pipe having inner and outer surface, thecombination comprising a. drive means engageable with one of said innerand outer surfaces for rotating the apparatus about the pipe,

. thrust exerting means engageable with the other of said inner andouter surfaces for urging the drive means toward said pipe, said thrustexerting means including individually adjustable rollers engageable withsaid other surface,

. support structure for said drive means and thrust exerting means,

. a first cutting tool and a head therefor carried by said supportstructure for movement toward and away from said other surface of thepipe, and

. other means including a spring to yieldably urge the head toward saidother surface of the pipe so that the cutting tool may have yieldablecutting engagement with the pipe as the apparatus rotates about thepipe.

2. The combination of claim 1 including a second cutting tool carried bythe head, said tools having positions of alternate cutting presentationto the pipe.

3. The combination of claim 2 wherein one of said tools comprises agroove cutter.

4. The combination of claim 3 wherein the other of said tools comprisesa pipe cut-off tool.

5. The combination of claim 2 including means pivotally supporting saidtools on the head for said alternate presentation to the pipe.

6. The combination of claim 1 wherein said other means includes a firstcarrier to support the spring for adjustable movement toward and awayfrom the pipe.

7. The combination of claim 6 wherein said other megns in ludgs a secondc gier o atively con ected wit the ea and came y the irst carrier oradjustable movement displacing the head toward and away from the pipewhile the spring continues to urge the head toward the pipe.

8. The combination of claim 1 including said pipe the inner surface ofwhich is engaged by the drive means of the outer surface of which isengaged by the thrust exerting means.

9. The combination of claim 1 wherein said thrust exerting rollers arecarried by holders movable on nd relative to said support structurealong arcuate paths to advance and retract the rollers generally normalto the pipe outer surface.

10. The combination of claim 9 wherein one of said rollers has surfacegrooving angled to urge the apparatus endwise toward the pipe end inresponse to rotation of the apparatus about the pipe.

11. The combination of claim 9 wherein said thrust exerting meansincludes manually actuable elements independently adjustable to displacesaid holders along said paths.

12. The combination of claim 1 including a removable and selected widthspacer carried by the head to space the cutting tool at a selecteddistance from the pipe end.

13. The combination of claim 9 including pivoted links swingablysupporting said holders for movement along said arcuate paths which arecircular.

l l t l

1. In apparatus for cutting pipe having inner and outer surface, thecombination comprising a. drive means engageable with one of said innerand outer surfaces for rotating the apparatus about the pipe, b. thrustexerting means engageable with the other of said inner and outersurfaces for urging the drive means toward said pipe, said thrustexerting means including individually adjustable rollers engageable withsaid other surface, c. support structure for said drive means and thrustexerting means, d. a first cutting tool and a head therefor carried bysaid support structure for movement toward and away from said othersurface of the pipe, and e. other means including a spring to yieldablyurge the head toward said other surface of the pipe so that the cuttingtool may have yieldable cutting engagement with the pipe as theapparatus rotates about the pipe.
 2. The combination of claim 1including a second cutting tool carried by the head, said tools havingpositions of alternate cutting presentation to the pipe.
 3. Thecombination of claim 2 wherein one of said tools comprises a groovecutter.
 4. The combination of claim 3 wherein the other of said toolscomprises a pipe cut-off tool.
 5. The combination of claim 2 includingmeans pivotally supporting said tools on the head for said alternatepresentation to the pipe.
 6. The combination of claim 1 wherein saidother means includes a first carrier to support the spring foradjustable movement toward and away from the pipe.
 7. The combination ofclaim 6 wherein said other means includes a second carrier operativelyconnected with the head and carried by the first carrier for adjustablemovement displacing the head toward and away from the pipe while thespring continues to urge the head toward the pipe.
 8. The combination ofclaim 1 including said pipe the inner surface of which is engaged by thedrive means of the outer surface of which is engaged by the thrustexerting means.
 9. The combination of claim 1 wherein said thrustexerting rollers are carried by holders movable on nd relative to saidsupport structure along arcuate paths to advance and retract the rollersgenerally normal to the pipe outer surface.
 10. The combination of claim9 wherein one of said rollers has surface grooving angled to urge theapparatus endwise toward the pipe end in response to rotation of theapparatus about the pipe.
 11. The combination of claim 9 wherein saidthrust exerting means includes manually actuable elements independentlyadjustable to displace said holders along said paths.
 12. Thecombination of claim 1 including a removable and selected width spacercarried by the head to space the cutting tool at a selected distancefrom the pipe end.
 13. The combination of claim 9 including pivotedlinks swingably supporting said holders for movement along said arcuatepaths which are circular.